The present invention relates to an automatic inflating lifesaving buoy, which is automatically inflated upon using to form a lifesaving buoy and can be easily handled.
The conventional lifesaving buoys have been mounted on ships and the like in such a state that the lifesaving buoys have been already formed by charging air into a buoy-forming bag and sealing the air to inflate the bag or by charging a light weight substance, such as cork, foamed rubber, foamed plastics and the like and if necessary, said lifesaving buoys are connected to a saving rope. These lifesaving buoys are exposed to sun light and wind containing salt in the state where the lifesaving buoys have been already inflated, so that the deterioration of the material forming the buoy is rapid and it is necessary to continually check their condition and further even upon using, such buoys are relatively bulky and light in weight, so that it is difficult to throw the lifesaving buoy accurately and far. Moreover, a large area is necessary in a convenient location for storing lifesaving buoys so as to be able to use the buoys at an urgent time in the inflated bulk state. Accordingly, the conventional lifesaving buoys have a variety of problems.
Therefore, a variety of lifesaving buoys which are automatically inflated upon using to form said buoys, have been proposed in order to solve these problems. For example, there are U.S. Pat. Nos. 2,786,599, 3,693,202, 3,812,546 and 3,449,777. However, all these devices use a compressed gas bomb as the gas generating source, so that there are problems of gas leakage, lowering of speed for discharging gas under a low temperature circumstance and the like.
Furthermore, the automatic puncturing mechanism of the bomb employs a water soluble substance as a stopper for a spring-loaded puncturing needle (U.S. Pat. Nos. 2,786,599, 3,693,202) or one in which puncturing the pin is actuated by explosive material which is detonated by utilizing a sea water-activated battery (U.S. Pat. No. 3,449,777). In any of these prior art devices there are problems in safety, reliability, rapid actuating ability and the like.
An explanation will be made in more detail with respect to the above described prior art devices. For example, the lifesaving buoy described in U.S. Pat. No. 3,693,202 comprises a gas bomb containing a compressed gas, such as freon gas, or liquefied carbonic acid gas, an automatic opening mechanism for the bomb and a buoy (composed of a flexible polyvinyl chloride sheet), which is inflated by the gas discharged from the gas bomb. The automatic opening mechanism comprises a spring-loaded nozzle capable of puncturing the sealed opening of the gas bomb, the release of which is restrained by a soluble substance. When such a lifesaving buoy is thrown in water, the water soluble substance is dissolved, the nozzle is released and punctures the sealed opening of the gas bomb, whereupon the discharged gas enters into the polyvinylchloride sheet to inflate it and to form the lifesaving buoy.
However, in the above described lifesaving buoy, the automatic inflating system directly utilizes the gas contained in the gas bomb, so that under low temperature, as in winter, the discharge speed of the gas from the gas bomb is slow and it is difficult to inflate the buoy within the necessary time. Further, the charged gas probably leaks from the gas bomb during storage over a long period of time and since the automatic opening mechanism of the gas bomb is actuated by the dissolution of the water soluble solid, a relatively long time is necessary for dissolving the water soluble solid. Therefore, time until the lifesaving buoy is dropped onto sea and is inflated, is not instantaneous but is slow. Since unevenness of the actuating time is large, a safety member is necessary, so that the safety member must be pulled out for the actuation. Thus, this prior art has a variety of drawbacks.
Lifesaving projectile apparatus propelled by the explosive force of gun, in which a gas is generated from a gas generating composition which reacts with a liquid, has been disclosed in U.S. Pat. No. 3,496,580 without using the above described compressed gas. However, in this apparatus, lithium hydride to be used as the gas generating agent is unstable against moisture and the generated gas is hydrogen which is an inflammable dangerous gas, so that this apparatus is disadvantageous in view of safety and reliability. Furthermore, the gas generating composition generates the gas through the reaction with a liquid, such as water, so that this apparatus is readily influenced by temperature and particularly, when water is used, water freezes under a weather condition of lower than 0.degree. C and the reaction with the gas generating composition, such as lithium hydride cannot be fully expected. Thus, there yet remain problems in the above described prior art devices, that is, lowering of the speed for discharging gas and reliability in discharging of the gas.